﻿    <p>
      The <em>IfcExtendedProperties</em> is an abstract supertype
      of all extensible property collections that are applicable to
      certain characterized entities. Instantiable subtypes of
      <em>IfcExtendedProperties</em> assign the property
      collection to a particular characterized entity.
    </p>
    <blockquote class="note">
      NOTE&nbsp; Extensible property collections are provided for
      materials and profiles.
    </blockquote>
    <p>
      Instantiable subtypes have a set of <em>Properties</em>, each
      providing property name, value and unit and other instance
      information, depending on the subtype of IfcProperty
      referenced.
    </p>
    <blockquote class="history">
      HISTORY&nbsp; New entity in IFC4.
    </blockquote>